An analytical RPLC method for sesquiterpene lactones in Arnica montana has been extended to include quantitative analyses of dihydrohelenalin esters. LC-ESI-MS-MS distinguished the isomeric helenalin and dihydrohelenalin esters. The dihydrohelenalin esters have lower response factors for UV detection than do helenalin esters, which must be taken into account for quantitative analyses. Analyses of flowers from 16 different wild populations of A. montana in Spain showed differing proportions of helenalin and dihydrohelenalin esters. For the first time a chemotype with high levels of helenalin esters (total helenalins 5.2-10.3 mg/g dry weight) is reported in Spanish A. montana. These samples were from heath lands at high altitude (1330-1460 m), whereas samples from meadows and peat bogs at lower altitudes were the expected chemotype with high levels of dihydrohelenalin esters (total dihydrohelenalins 10.9-18.2 mg/g). The phenolic compounds, both flavonoid glycosides and caffeoylquinic acids, in Spanish A. montana are reported for the first time. The levels of several of these compounds differed significantly between samples from heath lands and samples from peat bogs or meadows, with the heath land samples being most similar to central European A. montana in their phenolic composition.

Agroforestry is a sustainable land management system that should be more strongly promoted in Europe to ensure adequate ecosystem service provision in the old continent (Decision 529/2013) through the Common Agricultural Policy (CAP). The promotion of the woody component in Europe can be appreciated in different sections of the CAP linked to Pillar I (direct payments and Greening) and Pillar II (rural development programs). However, agroforestry is not recognised as such in the CAP, with the exception of the Measure 8.2 of Pillar II. The lack of recognition of agroforestry practices within the different sections of the CAP reduces the impact of CAP activities by overlooking the optimum combinations that would maximise the productivity of land where agroforestry could be promoted, considering both the spatial and temporal scales.

Silvopastoral systems are a form of multiple purpose land use, one function of which can be to reduce the risk of forest fires, which continue to be a threat to forests. In Spain, from 1991-2000 more than 175 000 ha were destroyed by fire annually, a third of this being woodland. Control of the undergrowth, which acts as a plant fuel for fire, should be made through prevention techniques that include cutting, controlled burning and controlled grazing. Grazing can also be a cause of fire, but when a suitable livestock breed is chosen and correctly managed, with animals which will reduce the understorey, it can prevent fires. These animals can also create income from meat production, as well as bringing other benefits, such as landscape enhancement, improved access and production of secondary products such as mushrooms. In long-term research in Galicia on this technique over four decades, encouraging trials have been conducted with goat, horse, sheep and pig grazing in Eucalyptus globulus, Pinus pinaster, Pinus sylvestris and Pinus radiata plantations. In this chapter, the key findings of this research will be presented alongside research on the same topic from elsewhere. Current research on grazing management of horses in a Pinus radiata plantation showed that, in the medium term, control of understorey is important and there was no difference between continuous and rotational grazing.

The threatened European species Arnica montana L. is a plant much appreciated in the pharmaceutical industry, Galicia (North-Western Spain) being one of the main supply regions. Two chemotypes based on the content of sesquiterpene lactones have been found in this area: a chemotype dominated by helenalins, common in Central Europe, and another dominated by dihydrohelenalins, only found currently in Galicia. The aim of this work was to analyse the phylogenetic relationships and genetic diversity of Arnica montana in Galicia and their concordance with previous biochemical and environmental information. Two polymorphic chloroplast markers were sequenced in individuals from populations showing significant biochemical differences and situated in different environments (heathland, hay-meadow and peatland). Three haplotypes, different from those previously described in Europe, were found in Galicia and our results suggest that one of them could be ancestral inside the species. Significant population differentiation was detected in the studied area but genetic diversity within populations was low, only showing variability in heathland populations. This study is the first one describing the genetic diversity of Arnica montana in the extreme SW of Europe. The results suggested the presence of two different genetic groups (one of them ancestral) and were congruent with the two chemotypes described. Plants from heathlands displayed the highest variability because the two chemotypes were present in them. Future design of conservation and economical management plans for this threatened species should take into account this genetic variability and prioritize further genetic and chemical characterizations across the distribution range of the species.

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